Drill



A. L. HAWKESWORTH.

DRILL APPLICATION FILED NOV. 2l, 1921.

1,422,265., v Patented July M, 1922.

. 2 S EETSSHEET l.

A. L. HAWKESWORTH.

DmLL.

- APPLICATJON FILED NGV. 2l, 192i. 1,422,265., I Patented July M, 1922.

2 SHEETS-SHEET 2.

rceives the torgue; Fig. 2 is a side elevationv entre' srernsrnrrlnr oeste-e.

ARTUR L HAWFKESWR'EH, Oli' BUTTE, E'INTANA.

'A narra...

meegaan Specification of Letters retient. Pgjggmhgqj J why' .1j je 119220 vapinclinan sie@ november 21,'11921. ser-iai no sicrea To all whom it may concern: j 4 v 'Be it known that I, ARTHUR L. HAWKES WORTH, a citizen of the lUnited States,-resid ing at Butte, in the county vof Silverbow and State of Montana, have. invented certain newfand useful Improvements in Drills, ofv

therefor arises, as for example/where a bit must be removed -to be sharpened and a new bit substituted, or when it is desired to take ed the bit for safe-keeping, or forany other reason. The .present improvement possesses many advantages from a structural stand-v point as will be morefully apparent from the following detailed description in connection with the accompanying drawings, in which j l Figure 1 represents anelevational view of my improved drill turned to present the ends of the dove-tail tongue on the bit and complementary groove .in shank which reof the drill; ig. 3' is an elevational view of the drill turned to present the end of the vconicaltongue on the bit which 'is adapted to be wedged into the conical4 hole inthe shank for locking the bit on the shank; Figs.v

t and 5 are detached side elevations ofthe bit and shank respectivelyiFigi-. is a bot- -to'ni plan Viewof the bit; F ig.-'7 is'a'n end view of the shankshowing in top plan 'the formations which'cooperate with those on the bit for locking the latter on the-shank; Fig. 8 is an elevational view of a modified form of the'invention; Fig. 9 is an elevationalview ofthe modified form of drill turned to present the end of taper tongue and groove of bit and shank respectively; Figs. l0 and 11 are detached elevational views ofthe modified form of bit and shank respectively; Fig. 12 is a. bottom plan vof'bit shown in Fig. 10 and Fig. 13 is an end view I. ofthe shank shown inFig. 11.

to the drawings, and for the igs. 1 to k7 inclusive. .1 represents liteferrin"l present to,

a drill-bar or shank provided with a central passageway or duct a for the How of water usually ,employedv in drilling operations as well understood in the art. The shankterinmates at itsbitsupporting end in a zigzag formation comprising a surface inclined away from the general direction of the 'cuttin 'end of the-.tool andA toward the longitu inal vaxis yof the shank, and a surface 0 disposed in a plane parallel with surface ,andinclined away from the general direction of the cutting endof the tool and awa. from the axis of the shank. The'surface Gli lies fon one 'side of the axis -of the shank, Y

andthe surface c lies on the=other side of said axis, the surfaces a and being connected by a plane surface d inclined in a direction opposite to that of surfaces and c. rlhe surface d is substantially perpendicular to surfaces and c. rFhe disposition of surfaces -c and d results in the formation of anabutment wall 2 on one side of the shank axis through which extends a ltapered or conical holeo having the innermost part .of

its bounding wall extending in the same plane Vwith that of surface b. A dove-tail groove 3- is formed in the surface b extending from one side thereof toward the axis of the shank. The faces b and 0 are adapted to form the 4supporting surfaces for a bit 4 which is provided with formations comple mental-y to those on the shank just described, the bit formations comprising parallel inclined faces e and f joined by a face L substantially perpendicular to them. Y

rFhe faceh has projecting' from it a conical tongue 5, the outermost point in the periphery of which lies in the same plane as the face e, said tongue being adapted to wedge in the taper hole o when the bit and shank are assembled. it. dove-tail tongue 6 projects outwardly from the face 'c and en v tends from one side ofsaid 'face toward the Abit, said port registering with port a to forni acontinuous passage through the drill when the bit is in place on the shank.

ln assembling-bit and shank the bit is passedV across the axis of the shank with the tongue 5 pointed into the hole 0, and as faces e and f ride over facesba'nd c respectively, the tongue 5 will gradually be wedged in the hole o and the tongue 6 will ride in l the groove 3. @bviously a clearance a between faces Z and it must be provided-les well as a clearance af between the ends of tongue 6 -`and groove 3 so that these respec# tive surfaces 'will not engage before the tongue becomes tightly1wedged in the hole o.

In Figs. 8 to V13 inclusive show a'modified formA ofthe invention, 1n which faces-l c and f" are arched instead of plane. This will assist in preventing relative 'movement Y between 'bit and shank 'under 'tortional to, saidv shank bein strains such asareincurred in rotary'drilling.' 4 i A.

Obviously the formations on bit and shank above set forthA to tighten while in use but,

nevertheless, to be easilydetached when desired. i 20 Having described tool adapted tobe ,detachably secured thereprovided-on the cuttin end thereof with a zigzag formation inc uding an abutment wall providedwith a tapered hole, said cutting ,tool being provided wit'h complementary lformations for cooperating with those on .the shank, and

having' .a tapered tongueA adapted to vbe shank are assembled.

wedged in the aforesaidl hole when tool and vto, said shank terminating at one-end in a zigzagl formation comprising two incl-ined faces disposed in parallel planes and an-'opfv positely inclined 'face connecting the two I faces afore'said,an abutment wall bounded by two Vadjacent faces, a taperedhole'in said abutment wall, saidv cutting tool being provided .with a formation complementary 1. In combination with a shank, a cuttingv I to'that on the shank comprising two faces in parallelplanes and a .connecting face, ,the last mentioned face having a'tapered tongue projecting from itan'd adapted -to be wedged are assembled. i i f 3. AIn combination 145" 1n 'the aforesaid hole wh'enshan'k and tool' 'i zi 'za' formation com risin two vfacesone said faces inclining inthe same general diof which is' plane and the other. arcuate, Y

rection andbeing connected by v'an oppositely inclined face and-an abutment wall provided with a tapered'hole, said cutting tool terminating in fa complementary formation com. prising Afaces complementary to those'on the' shank, and a tapered tongue projecting from 'one of said complementary faces, said tongue my invention, I 'claim being adapted to -wedge in the aforesaid hole .when bit and-Shank are assembled.

4. .In combination with'a shank, a cutting tool adapted to be detachably secured thereto, said shankterminating at one end in a zigzag formation comprising two inclined faces disposed in parallel planes and connected by an oppositely inclined face, and an abutment Wall, one of said faces being provided with a froove .and the abutment` hereunto affix my ARTHUR L.v HAWKESWORTH.

'7 5 wedged in the aforesaid hole, and a second- 

